Since every Microsoft services available at Android & iOS, Why should any one buy a Lumia??

I've a L730, but since Microsoft is very kind on Android & iOS platforms past 1 year and providing every services to these platforms which made the windows phone unique about it, like cortana, office, outlook, here Maps, mixradio, etc. why anyone should buy a Lumia? I always thought was it a mistake to buy a windows phone.
Any suggestions guys?

Not everyone wants static grids of tiles on their home screens
Not everyone wants to be tied into Apple's tight view of the world
Not everyone wants to be tied into Googles open/insecure view of the world
Not everyone wants to buy a new handset every time they want the next major version of software
Not everyone feels the need to blindly follow whatever their friends are doing

Simple, Windows Phone makes you different whether its a good or bad thing. Although there isn't really substantial effect in going with Windows Phone/W10 right now since it is still under a big development. As a multi os user I suggest you to part ways with Windows Phone OS for now, go with IOS or Android then come back soon to windows phone if you think its finally worth owning one. Or, if you can, be a multi os user like me and you'll get the best of each world.

I tried making the switch to iOS about a year ago and was frankly disappointed. Put simply, I like the Windows Phone/Mobile Operating System better. It gives me more options for customization and personalization than iOS does, but isn't as open as Android. The "app gap" is real, no matter what some on this forum might say, but having greater access to apps was not enough to overcome the fact that I simply did not like iOS, so I switched back.